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[Xtensa Patch] Use custom copy function for vinsns


While looking at the performance issues for my last check in, I noticed several other performance bottlenecks in the Xtensa port.

I have committed this patch which addresses one of them: vinsns are sized for worst case configurations, but the vast majority of configurations aren't worst case. The enclosed patch maintains the worst-case sizing, but adds a custom copy function for this data structure which only copies the actual case, thereby improving performance substantially on most configs.

Sterling

2009-08-20 Sterling Augustine <sterling@jaw.hq.tensilica.com>

	* config/tc-xtensa.c (xg_copy_vinsn): New function.
	(finish_vinsn): Call xg_copy_vinsn.
Index: gas/config/tc-xtensa.c
===================================================================
RCS file: /cvs/src/src/gas/config/tc-xtensa.c,v
retrieving revision 1.113
diff -u -p -r1.113 tc-xtensa.c
--- gas/config/tc-xtensa.c	19 Aug 2009 16:10:46 -0000	1.113
+++ gas/config/tc-xtensa.c	20 Aug 2009 18:08:49 -0000
@@ -527,6 +527,7 @@ static int get_num_stack_literal_bytes (
 /* vliw_insn functions.  */
 
 static void xg_init_vinsn (vliw_insn *);
+static void xg_copy_vinsn (vliw_insn *, vliw_insn *);
 static void xg_clear_vinsn (vliw_insn *);
 static bfd_boolean vinsn_has_specific_opcodes (vliw_insn *);
 static void xg_free_vinsn (vliw_insn *);
@@ -6653,7 +6654,6 @@ xg_find_narrowest_format (vliw_insn *vin
 
   xtensa_isa isa = xtensa_default_isa;
   xtensa_format format;
-  vliw_insn v_copy = *vinsn;
   xtensa_opcode nop_opcode = xtensa_nop_opcode;
 
   if (vinsn->num_slots == 1)
@@ -6661,7 +6661,8 @@ xg_find_narrowest_format (vliw_insn *vin
 
   for (format = 0; format < xtensa_isa_num_formats (isa); format++)
     {
-      v_copy = *vinsn;
+      vliw_insn v_copy;
+      xg_copy_vinsn (&v_copy, vinsn);
       if (xtensa_format_num_slots (isa, format) == v_copy.num_slots)
 	{
 	  int slot;
@@ -6696,7 +6697,7 @@ xg_find_narrowest_format (vliw_insn *vin
 	    }
 	  if (fit == v_copy.num_slots)
 	    {
-	      *vinsn = v_copy;
+	      xg_copy_vinsn (vinsn, &v_copy);
 	      xtensa_format_encode (isa, format, vinsn->insnbuf);
 	      vinsn->format = format;
 	      break;
@@ -11702,6 +11703,16 @@ xg_clear_vinsn (vliw_insn *v)
 }
 
 
+static void
+xg_copy_vinsn (vliw_insn *dst, vliw_insn *src)
+{
+  memcpy (dst, src, 
+	  offsetof(vliw_insn, slots) + src->num_slots * sizeof(TInsn));
+  dst->insnbuf = src->insnbuf;
+  memcpy (dst->slotbuf, src->slotbuf, src->num_slots * sizeof(xtensa_insnbuf));
+}
+
+
 static bfd_boolean
 vinsn_has_specific_opcodes (vliw_insn *v)
 {

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